(1) Field of the Invention
The present invention relates to spirit levels and more particularly to illumination adapters which are arrangable on a plurality of different spirit levels.
(2) Prior Art
Craftsmen, such as carpenters, cabinet makers, plumbers, sheetmetal workers, masons and the like, use spirit levels. Their tools may in fact include three or four different types or lengths of levels.
These levels may occasionally be needed in dark work areas, where the glass sight openings are difficult to see. It may also be difficult to see the work which itself is being leveled, as well as handling the level, hindering the making of any marks or adjustments to the workpiece and the like.
An early attempt at lighting a level is shown in U.S. Pat. No. 794,753 to Stetson, which shows a spirit level with a built-in battery and light for illuminating the bubble glass. This arrangement permits only the level glass to be lighted, and is not articulable for work surfaces being levelled.
A later attempt at providing light for a spirit level is shown in U.S. Pat. No. 2,205,733 to Sauter et al, wherein a pair of batteries hold a pair of bulbs inside the level housing, against the sight openings. Again, there is no ability for moving the lights with respect to the sight openings and/or the level itself or the elements that it is mused to level.
U.S. Pat. No. 2,607,882 to Arnold discloses an illuminated level, wherein an attachment unit is connected to an "un-lit" spirit level to light the sight openings. This is an improvement over the art, but it is limited in use to a single style or dimension of level where the sight openings are a particular distance apart. The attachment is not adaptable to different size levels with varying spaces between their respective sight openings. The light attachment of Arnold is utilizable for the one level that it is made for and nothing else.
U.S. Pat. No. 3,003,054 to Hubbard also discloses an illuminated spirit level, with an electric bulb in a channel support, for illuminating a sight opening.
None of the prior art shows an adaptor light assembly which may be movable from one type of level to another, which may be of a different size or style, and which light is articulable to help light a work area being levelled.
It is an object of the present invention to overcome the disadvantages of the prior art by providing a transferrable light adapter assembly which a craftsman may use on any one of several different spirit levels he has in his tool supply and which assembly may be utilized to light the work area as well.